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Rajesh Singh
Rajesh Singh

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SlimPDF - A Lightweight and Privacy-Friendly PDF Compressor

#python #webdev #productivity #opensource

If you’ve ever tried emailing a PDF only to see the dreaded “File size too large” popup, welcome to the club.
And if you’ve ever uploaded a suspiciously important PDF to an online “FREE PDF COMPRESSOR 🔥” website, only to worry whether your passport is now the newest NFT on the dark web… welcome to the club’s VIP lounge. 😅

At some point, I got tired of choosing between:

  • Bloated PDFs, or

  • Sending sensitive documents to random cloud services

So, like any developer on a mission, I built my own solution.

Meet SlimPDF: a tiny, elegant, local-first PDF compressor app built using Flask and Ghostscript, designed to shrink your PDFs safely and privately, everything stays on your machine.

🔗 GitHub Repo: https://github.com/rajks24/SlimPDF

🎯 Why I Built SlimPDF

Most PDF compression tools are convenient — but they run on someone else’s server.
That’s fine for a holiday brochure… but not so fine for:

  • Passport scans
  • Visa documents
  • Work contracts
  • Medical files
  • Bank statements
  • School forms

Anything that makes your anxiety go up when uploading it online 😬

I needed a tool that:

✔ Works offline
✔ Compresses PDFs instantly
✔ Never uploads anything anywhere
✔ Is simple enough for anyone to use
✔ And customizable enough for any dev to extend

Thus, SlimPDF was born.

⚡ What SlimPDF Does

SlimPDF is a minimalistic web app (built with Flask) where you:

  1. Upload a PDF
  2. Click “Compress”
  3. Instantly download a lighter version of it

It quietly uses Ghostscript under the hood, a battle-tested tool that the industry has trusted for decades for PDF processing.

No ads.
No tracking.
No server logs.
No hidden “your files will be deleted in 24 hours” promises.
Just pure, local PDF slimming.

🚀 Quick Start to run it locally

If you want to try the app yourself:

Clone the repo

git clone https://github.com/rajks24/SlimPDF
cd SlimPDF
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Install dependencies

pip install -r requirements.txt
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Install Ghostscript

macOS (brew):

brew install ghostscript
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Ubuntu/Debian:

sudo apt install ghostscript
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Windows:
Download the Ghostscript installer:
https://ghostscript.com/releases/index.html

Run the app

python main.py
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Visit:
➡️ http://localhost:5000

Now you can compress PDFs right from your machine.

🎉 Final Thoughts

SlimPDF started as a weekend project… but quickly became something I personally use regularly.
We all deal with PDFs, and we all care about privacy, so building a tool that combines both felt meaningful.

If you:

  • Have ever been anxious uploading personal PDFs online
  • Want a lightweight, open-source, local PDF compressor
  • Or want to learn Flask through a practical example …then SlimPDF might be worth checking out.

🔗 GitHub Repo: https://github.com/rajks24/SlimPDF

⭐ If you like it, consider "like" the repo, it helps others find it too!

Thanks for reading, and may your PDFs stay slim and your stress stay low. 😄

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